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HTML5 video not supported for youtube

  • 10 replies
  • 1 has this problem
  • 11 views
  • Last reply by James

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I have no plug ins or add ons in my Firefox. I cannot play HTML5 videos at all. "Your browser does not recognize any of the video formats available."

I have no plug ins or add ons in my Firefox. I cannot play HTML5 videos at all. "Your browser does not recognize any of the video formats available."

All Replies (10)

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What do you get on https://www.youtube.com/html5/ as all check marks should ideally be blue.

if at least a couple are red then you may not have installed FFmpeg as it is not normally installed during a Linux distro install. Ubuntu for example has a Ubuntu Restricted Extras for this.

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James said

What do you get on https://www.youtube.com/html5/ as all check marks should ideally be blue. if at least a couple are red then you may not have installed FFmpeg as it is not normally installed during a Linux distro install. Ubuntu for example has a Ubuntu Restricted Extras for this.

I see six check boxes. The middle two are not checked ( H.264 and MSE H.264).

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type about:config in address bar and search for:

  • media.mp4.enabled
  • media.wmf.enabled

make sure all true

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FFus3r said

type about:config in address bar and search for:
  • media.mp4.enabled
  • media.wmf.enabled
make sure all true

media.mp4.enabled is true media.wmf.enabled does not appear on the list

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make sure there is no space after or before

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No space

media.wmf.enabled

Does not appear on the config list

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No worries, "wmf" is for Windows users.

You need an FFmpeg component for Linux for Firefox to decode H.264 video, as James mentioned. I honestly don't know the best way to install that, but your package manager might be a starting point.

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whiteladyeowyn said

James said
What do you get on https://www.youtube.com/html5/ as all check marks should ideally be blue. if at least a couple are red then you may not have installed FFmpeg as it is not normally installed during a Linux distro install. Ubuntu for example has a Ubuntu Restricted Extras for this.

I see six check boxes. The middle two are not checked ( H.264 and MSE H.264).

So you may likely not have FFmpeg installed as it provides the codecs needed.

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Okay, I found some pages talking about downloading the FFmpeg you all mentioned, but that looks like a lot of complicated coding to me. something beyond my skill.

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Look in your package manager. As you appear to be using Ubuntu or one or the flavours of it it may be in the Ubuntu Restricted Extras as I mentioned.

https://help.ubuntu.com/community/RestrictedFormats https://en.wikipedia.org/wiki/Ubuntu-restricted-extras